1. Field of the Invention
The invention relates to a device for implanting at least one row of X radioactive seeds and Y non-radioactive spacers with X∈[1, 2, . . . ] and Y∈[0, 1, . . . ] in a desired configuration to a desired location in an animal body for effecting radiation therapy of cancerous tissue in said body, said device comprising: at least one elongated hollow needle with an open distal end to be inserted towards said desired location in the body and with a proximal end to be connected to a seed loading apparatus; and at least one pushing element for implanting during retraction of the elongated hollow needle said row of radioactive seeds and non-radioactive spacers from said seed loading apparatus through said hollow needle towards said location.
The invention moreover relates to a seed loading apparatus provided with an implanting device according to the invention as well as to a row of X radioactive seeds and Y non-radioactive spacers with X∈ [1, 2, . . . ] and Y∈[0, 1, . . . ] in a desired configuration, wherein said seeds and spacers are accommodated in a tube-shaped element according to the invention.
2. Description of the Background
In the European patent application no. 1070519 in the name of the applicant of this application an apparatus for implanting radioactive seeds in e.g. the male prostate gland is disclosed. Under ultrasound guidance using an ultrasound probe and using a first template implant needles, hereinafter needles, are placed in the prostate gland. Under fluoroscopy the positions of the needles are checked and for every individual needle the length and configuration of the row or train of seeds/spacers is determined using a radiation therapy treatment module.
In order to finalize the implant procedure each row of seeds/spaces is urged through it's corresponding needle towards the open distal end of the hollow needle in the prostate gland using a pushing element. Subsequently the pushing element is fixed and the hollow needle is retracted over a distance equal or slightly greater than the length of the row of seeds/spacers, thereby introducing the row of seeds/spacers at it's intended postion within the prostate gland.
Next the pushing element is withdrawn into the seed loading unit for pushing a next seed-spacer row through another needle into the prostate gland. The delivery of subsequent seed/spacers rows in the prostate gland continues until each needle has been retracted and a number of seed-spacer rows equal to the number of needles has been positioned at different locations within in the prostate gland.
The known apparatus is then disconnected and the needles are retracted from the patient completely. A final control/check of the geometry/presence of the implanted seeds in the prostate gland is performed under fluoroscopy or another imaging technique and after removal of the ultrasound probe the patient is hospitalized for recovery.
Examples of configurations of a row of radioactive seeds and non-radioactive spacers are for example disclosed in the International Patent Application Nos. WO02/20089, WO00/09211, WO99/59675 and in the U.S. Pat. No. 4,815,449.
Each row of radioactive seeds and non-radioactive spacers as disclosed in the above prior art patent publications has the disadvantage that after insertion into the body or near to the tissue to be irradiated the inserted seeds and spacers are only accommodated/enveloped by tissue of the body.
Furthermore all rows of seeds/spacers as disclosed in the cited prior art patent publications can only be configured in a seeds/spacer configuration consisting of a repeated configuration “seed, spacer, seed, spacer, . . . ”. This gives less flexibility in configuring the treatment plan and seed/spacer trains in another configuration/sequence.
That may have a consequence that upon movements of the body in which the row of radioactive seeds and non-radioactive spacers has been inserted the radioactive seeds and non-radioactive spacers may move through the body/the tissue to be irradiated and as a consequence of these movements undesired irradiation of other tissue will occur.
This will be disadvantageous for the therapeutic treatment since the distribution of the radioactive seeds and non-radioactive spacers in each row has been calculated with great accuracy in order to reach an optimal result in respect of the irradiation of the tissue to be treated. In general not one but a number or even a great number of rows of radioactive seeds and non-radioactive spacers, each arranged with a predetermined pitch, is inserted in order to irradiate the tissue, often cancerous tissue and their exact position within the tissue has been calculated using a specific radiation therapy treatment module in order to spare/avoid undesired radiation of fragile tissue or organs, e.g. the urethra, bladder or rectum during the treatment of the prostate gland.
There is therefore a need for rows of radioactive seeds and non-radioactive spacers for brachytherapeutic treatment of tissue with radioactive radiation in which mutual displacement of the seeds/spacers after insertion of the row into the body is avoided due to e.g. movements of the patient or other disturbances within the body like swellings, blood circulation etc.